How can I implement rate limiting in my asyncio web scraping project?

How can I implement rate limiting in my asyncio web scraping project?

You can use the asyncio library along with aiohttp to manage your web scraping. To implement rate limiting, you can use a semaphore to control the number of concurrent requests.

Can you show me a code example for that?

Sure! Here's a simple example:

import asyncio
import aiohttp

async def fetch(session, url):
    async with session.get(url) as response:
        return await response.text()

async def main(urls):
    semaphore = asyncio.Semaphore(5)  # Limit to 5 concurrent requests
    async with aiohttp.ClientSession() as session:
        tasks = []
        for url in urls:
            tasks.append(fetch_with_limit(semaphore, session, url))
        return await asyncio.gather(*tasks)

async def fetch_with_limit(semaphore, session, url):
    async with semaphore:
        return await fetch(session, url)

urls = ['http://example.com'] * 100  # Example URLs
asyncio.run(main(urls))

What if I want to change the rate limit dynamically?

You can adjust the semaphore value based on your needs. For example, you could implement a function that updates the semaphore limit based on the response time or server load.